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本文研究了纤维素LiCl／DMAc体系的溶液特征。实验结果证明该体系具有良好的时间稳定性和热稳定性，能在常温下近30天内没有明显的粘度降低；在100℃高温下，4h不降解。同时测定了溶液的特性粘数和Huggins常数，Huggins常数在0．4～0．6之间，对比纤维素的铜乙二胺（Cuen）溶液，发现特性粘数[η]LICI/DMAc＞[η]Cuen，无扰尺寸ALiCi／DMAc＞ACuen，可见在LiCl／DMAc体系中，溶剂与纤维素分子表现出更强的相互作用力，分子链充分伸展。该体系的特性粘数、粘度常数不仅与温度、溶剂有关，而且是LiCl浓度的函数，具有与聚电解质溶液相类似的性质。这可能是因为纤维素分子链上的H质子和溶液中的Cl-离子相互作用，而使纤维素分子带上部分电荷，相互排斥而引起的。因此利用M－H方程测分子量，粘度常数的确立必须考虑诸多因素的影响，否则会导致分子量的高估。
In this paper, the solution characteristics of cellulose LiCl / DMAc system were studied. The experimental results show that the system has good stability of time and thermal stability, can not visibly reduce the viscosity at room temperature within 30 days; at 100 ℃ high temperature, 4h does not degrade. The intrinsic viscosities and Huggins constants of the solutions were also determined. The Huggins constants were between 0.4 and 0.6. It was found that the intrinsic viscosity [η] LICI / DMAc> [ η] Cuen and scrambled size ALiCi / DMAc> ACuen. It can be seen that in LiCl / DMAc system, the solvent and cellulose molecules show stronger interaction and the molecular chain is fully extended. The intrinsic viscosity and viscosity constants of the system are not only related to temperature and solvent but also to the concentration of LiCl and have similar properties as the polyelectrolyte solution. This may be due to the interaction between the H protons on the molecular chain of cellulose and the Cl- ions in the solution, causing the cellulose molecules to partially charge and repel each other. Therefore, using the M-H equation to measure the molecular weight, the establishment of the viscosity constant must consider the influence of many factors, otherwise it will lead to overestimation of the molecular weight.